Music lovers are often seeking to achieve the Western Electric sound on lower budgets. Some seriously consider making a 12a or 13a on a DIY basis. They become confronted with the woodworking skills required,  timber supply, expensive tooling construction and necessary jigs (There are 17 for the 13a….). But also the castings of the throat (that means making the casting molds…), brackets and fixtures to make the horn all come together.  I am well aware that just the tooling costs alone can be very scary….

WE555 drivers or GIP 555w replica are expensive but they happen to be the only serious candidates for the big WE wide range horns.
All this adds up quickly…somewhat restricting going ahead with the project on a DIY basis.
Kind of « almost » solutions exist and are easily accessible to the DIYer that rely on plywood, need so castings nor professional jigs and tools.
The 15a horn is one candidate. It’s a very simple plywood build, and available plans make for an easy challenge for the gifted DIYer. However the DIYer will be faced with the need for “castings”. Sheet steel is an alternative or cheaper brass ones can be found. In the case of the 15a the 1st two sections are made of cast iron. Sheet steel can be used for the second section. Castings are really mandadtory for the 1st one but in a pinch maybe sheet steel will do it? My guess is that this solution would require “serious” metal working skills. I’ve seen 15a using 2 inch driver, all wood build (including throats) albeit shorter air column. Maybe an option even if a far fetch from a true 15a with we555….
WE15a cast iron throats sections :
img_010413Audio cast iron parts for 13a and 12a :
Can we really make a proper WE horn using shortcuts? Can we really consider that Western Electric used cast iron when cheaper options existed? Personally, I think not….but who knows?
To get a small taste of the bigger WE horns there is the WE66 horn.
The WE66 was never actually made by Western Electric. Here is the range of WE horns : WE_Horn_Compendium This WE66 horn was baptised by “Tatematsu Koge” as a “WE” in the 1980’s/90’s (maybe before?)
The WE66 is a sort of easy to build small and cheaper we12a. Or is it a shrunk 15a? What’s its big pro for the DIYer? It does uses cheaper drivers having a narrower bandwidth and all plywood build makes things easy.
The WE66 air column is one metre shorter than a WE12a, that’s a lot…. It does avoid the WE555 and its uncomparable qualities… cast iron throat, uses cheap plywood and requires no time consuming craftsmanship. So an option for the DIYer.
The WE66a simply needs some plywood to be cut, bent, glued and maybe nailed. The CNC masters can CAD draw and then order cuts online from shops doing online cutting from CAD….bingo…delivered flat pack to your door…The Ikea of horns?
The WE66 construction is described by French “DIY activists” Go here oh la la… it’s Français….pardonnez moi!
The 12a and 13a have no plans or blueprint. These horns were built by craftsmen using jigs shaping each piece of wood (several 100…) all glued together one by one. This is exactly what I do! I use the the very same jigs, tools, craft and materials… a long, slow and very rewarding process….
Some felt that WE66 needed to be corrected to be “better” and adapted for use with any  2” driver. Better meaning “flatter” bandwidth response. Okay….13Audio is all about “your sound” and the sacred microphone, computer and frequency response to “sweeps” is left aside. What counts is what you enjoy not what some technical feedback dictates. I have respect for the “aim at flat” crowd. Some of my audio pals have been in that world forever.
Part of the French audio crowd aim at flat and worked the SATO Horn, another easy and cheap build. You can see here a press article that was published on this SATO horn. This article has detailed plans and construction methods. The SATO sheds 1m50 (more than a lot…) of horn length versus the we12a.,..okay “encore” article in Français!
So budget approaches exist and with basic skills and minimal tooling it seems possible that the DIYers can “get things going” towards a big horn sound albeit with plywood that also means a resonating horn…unlike the solid wood 12a or 13a.
However, the WE66 or SATO are entirely different from the Western Electric 12a. They fundamentally differ in design and construction.
All fun….